Fix up notification to not spam or hide

Instead of hiding the success notification in vprint, it should print,
but not every time. This fix thottles the notification to ten seconds
per host.

[Fixes rapid7#731]

Author: todb

modules/auxiliary/spoof/llmnr/llmnr_response.rb

@@ -56,6 +56,7 @@ def initialize
 		self.thread = nil
 		self.sock = nil
 	end
+
 	def dispatch_request(packet, addr)
 		rhost = addr[0]
 		src_port = addr[1]
@@ -90,6 +91,7 @@ def dispatch_request(packet, addr)
 			print_status("type:	      #{llmnr_type.unpack('n')}")
 			print_status("class:	      #{llmnr_class.unpack('n')}")
 		end
+
 		if (llmnr_decodedname =~ /#{datastore['REGEX']}/i)
 			#Header
 			response =  llmnr_transid
@@ -122,12 +124,15 @@ def dispatch_request(packet, addr)
 				p.recalc
 
 				capture_sendto(p, rhost,true)
-				vprint_good("Reply for #{llmnr_decodedname} sent to #{rhost} with spoofed IP #{datastore['SPOOFIP']}")
+				if should_print_reply?(llmnr_decodedname)
+					print_good("#{Time.now.utc} : Reply for #{llmnr_decodedname} sent to #{rhost} with spoofed IP #{datastore['SPOOFIP']}")
+				end
 			close_pcap
 		else
 			vprint_status("Packet received from #{rhost} with name #{llmnr_decodedname} did not match REGEX \"#{datastore['REGEX']}\"")
 		end
 	end
+
 	def monitor_socket
 		while true
 			rds = [self.sock]
@@ -143,6 +148,22 @@ def monitor_socket
 			end
 		end
 	end
+
+
+	# Don't spam with success, just throttle to every 10 seconds
+	# per host
+	def should_print_reply?(host)
+		@notified_times ||= {}
+		now = Time.now.utc
+		@notified_times[host] ||= now
+		last_notified = now - @notified_times[host]
+		if last_notified == 0 or last_notified > 10
+			@notified_times[host] = now
+		else
+			false
+		end
+	end
+
 	def run
 		check_pcaprub_loaded()
 		::Socket.do_not_reverse_lookup = true
@@ -168,7 +189,9 @@ def run
 		while thread.alive?
 			select(nil, nil, nil, 0.25)
 		end
+
 		self.thread.kill
 		self.sock.close rescue nil
 	end
+
 end